Christmas and New Years...Italy, Spain, Portugal or ?

Well, weather-wise, Andalucia is the warmest, driest part of Europe. Barcelona on the Mediterranean coast has mild winters, while Portugal is on the Atlantic coast (to me that sounds cold and windy - check it out). Andalucia is well-connected to Madrid and Barcelona by train. Italy's winters are pretty mild, expect colder in the north and Florence because of its topography. I imagine Italy as more crowded around Christmas because of its importance to Catholics.

Sunset in Sevilla in the last week of December is 6.10-6.15 pm. In Rome its around 4.45 pm. Sevilla doesn't have much more daylight time, but because they are both on Central European time and Sevilla is so much farther east, you'll have effectively more daylight hours for sightseeing (does it matter so much if sunrise is at 7.30 or 8.30?).

Weather probably isn't going to be pleasant anywhere . I'd more make sure that you're in a big city between Dec 24th and Jan 1st, as there are a lot of official holidays in that time period and a lot of things close. Even attraction that almost never close are closed on Dec 24, 25, and Jan 1.

Madrid, Barcelona, Rome are places i'd focus on during those times. Lots of stuff to do indoors in case the weather is crappy, which again, it probably will be.

Weather-wise, the best area in Spain would be the Cannery Islands, one could Island hop and see the diverse nature areas as well as historic villages on each island. You could then spend New Years in Tenerife or Las Palmas.

From just a cultural standpoint, December would be a good time to visit Andalucia. It will definitely have less tourists than in the unbearable high summer months. Christmas is not such a big deal in Spain, more so in the south, so it won't be as crowded as say Roma. You could spend New Years in one of the bigger cities like Malaga or Sevilla.

If you want to specifically experience Christmas and New Years, then my recommendation would be Italy, specifically Roma. I was in Roma 5 years ago for Christmas and New Years and it was fantastic, the energy, the ambiance, and those Christmas markets in each square made for a really unique experience.

Why not try Argentina and Chile, it is nice and warm down there at that time of the year.

Chani, what a great summary. I would not have thought of Rome getting darker so much earlier than Spain.

I would just add that, in my opinion ,travelling my public transit around Italy is easier than Portugal, unless you are sticking to the main cities in Portugal. I can't speak for Spain.

We (couple in sixties with three adult children) spent last Christmas in Portugal in Lisbon and Porto. The temp was 50's-60's with sun most days so it was quite pleasant. We dressed in layers. Coming from MN the temperature was great! The only rain we had was one day in Porto and it did get windy and chilly, but not for the whole day.
Be aware that many places close by 3pm on the 24th and little is open on the 25th. We had a sunny nice day in Belem and the same in Sinatra so we felt very fortunate. In fact our first full day in Portugal we went to Cascais and it was lovely weather. We found public transportation to be easy between those cities and in Lisbon. Once in Porto, we walked everywhere.
While we haven't been in Spain over Christmas, we spent four weeks in Malaga in March and the weather was great in the 60's. We used Malaga as our base taking day trips in the area and then overnights to Seville and Granada. There is plenty to enjoy in Malaga and public transport is easy in the city and to other parts of Andalucia using the bus.
Have fun!